Fuel supply apparatus and fuel supply unit

ABSTRACT

A fuel injection apparatus for adjusting a flow rate of gas fuel and injecting and supplying the gas fuel through a discharge hole includes an open portion having a larger diameter than the discharge hole and being communicated with a downstream end of the discharge hole, and a separation suppressing member placed in the open portion. The separation suppressing member is configured to suppress generation of separation of the gas fuel flow when the gas fuel flows out from the discharge hole into the open portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromthe prior Japanese Patent Application No. 2015-023033, filed Feb. 9,2015, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a fuel supply apparatus and a fuelsupply unit for supply of gas fuel.

2. Related Art

In a fuel supply apparatus, during operation for supply of gas fuel, anabrupt change in cross-sectional area of a flow passage may causeseparation of flow or stream of the gas fuel, thereby generating gasflow sound (noise). To avoid such defects, there has been proposed afuel supply apparatus configured to reduce leakage of the noise to theoutside.

One example of the fuel supply apparatus of the above type is configuredsuch that a nozzle member is fixedly provided in a leading end portionof a valve housing internally including a gas fuel passage andaccommodating a valve element, and the nozzle member is provided with avalve seat member facing the gas fuel passage, a valve hole formedthrough a center portion of the valve seat member and to be opened andclosed by cooperation of the valve element and the valve seat member, afirst throttle hole communicated with an outlet of the valve hole, and anozzle hole communicated with an outlet of the first throttle holethrough a first annular step portion and having a larger diameter thanthe first throttle hole. The nozzle hole is provided with a secondthrottle hole communicated with a second annular step portion opposed tothe first annular step portion and having a smaller diameter than thenozzle hole. The second annular step portion and the second throttlehole are formed in an annular member that is separate from the nozzlemember and connected with the leading end portion of the nozzle member.

In the thus configured fuel supply apparatus, even if gas flow sound(noise) occurs due to the separation of gas fuel flow in the nozzlehole, the second annular step portion and the second throttle holeprovided in the leading end portion of the nozzle member can reduceleakage of the noise to the outside (see Patent Document 1).

RELATED ART DOCUMENTS Patent Documents

Patent Document 1: JP-A-2014-55569

SUMMARY OF INVENTION Problems to be Solved by the Invention

In the foregoing fuel supply apparatus arranged such that the secondannular step portion and the second throttle hole are provided in theleading end portion of the nozzle member, even if gas flow sound (noise)occurs due to separation of gas fuel flow in the nozzle hole, outsideleakage of such noise is prevented. However, the flow separation leadingto the generation of noise takes place. Thus, the generation itself ofthe gas flow sound could not be reduced. This may cause leakage of thegas flow sound to the outside.

The present invention has been made in view of the circumstances tosolve the above problems and has a purpose to provide a fuel supplyapparatus and a fuel supply unit capable of suppressing the generationof separation of gas fuel flow to reduce gas flow sound.

Means of Solving the Problems

To achieve the above purpose, one aspect of the invention provides afuel supply apparatus having a discharge hole and configured to adjust aflow rate of fuel gas and inject and supply the fuel gas through thedischarge hole, the apparatus comprising: an open portion formed with alarger diameter than the discharge hole and communicated with adownstream end of the discharge hole; and a separation suppressingmember configured to suppress generation of separation of flow of thegas fuel when the gas fuel flows out from the discharge hole into theopen portion, and wherein the separation suppressing member is placed inone of the open portion and the discharge hole.

In the fuel supply apparatus configured as above, the separationsuppressing member placed in the open portion or the discharge hole candecelerate the gas fuel in flowing out from the discharge hole into theopen portion, thereby suppressing the generation of separation of thegas fuel flow. This configuration can reduce gas flow sound which may becaused by the separation of gas fuel flow.

To achieve the above purpose, another aspect of the invention provides afuel supply unit including at least one fuel injection apparatusconfigured to adjust a flow rate of gas fuel and inject the gas fuel andan outflow passage in which the gas fuel injected from the fuelinjection apparatus is to be discharged, wherein the fuel supply unitcomprises a flow restricting member configured to forcibly direct thegas fuel discharged from a discharge hole of the fuel injectionapparatus into the outflow passage to flow in a radial direction of thedischarge hole.

In the fuel supply unit configured as above, the flow restricting memberdirects a gas fuel discharged from the discharge hole of the fuelinjection apparatus into the outflow passage to flow in a radialdirection. Thus, the gas fuel is dispersed in the outflow passage andalso decelerated. Accordingly, the separation of gas fuel flow can beprevented. This makes it possible to reduce the gas flow sound resultingfrom the separation of gas fuel flow.

Effects of the Invention

The fuel supply apparatus and the fuel supply unit according to thepresent invention can suppress the generation of separation of gas fuelflow and hence reduce the gas flow sound.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a fuel injection apparatus in a firstembodiment;

FIG. 2 is an enlarged sectional view of a valve seat member and itssurroundings;

FIG. 3 is a view of a first modified example;

FIG. 4 is a view of a second modified example;

FIG. 5 is a view of a third modified example;

FIG. 6 is a view of a fourth modified example;

FIG. 7 is a sectional view of a fuel supply unit in a second embodiment;

FIG. 8 is an enlarged sectional view of a leading end and itssurrounding of a fuel injection apparatus in a fuel supply unit; and

FIG. 9 is another enlarged sectional view of the leading end and itssurrounding of the fuel injection apparatus in the fuel supply unit.

DESCRIPTION OF EMBODIMENTS

A detailed description of preferred embodiments of a fuel supplyapparatus and a fuel supply unit embodying the present invention willnow be given referring to the accompanying drawings. The presentembodiment shows an example that the present invention is applied tosupply a gas fuel (e.g., hydrogen) to a fuel cell (not shown).

First Embodiment

A schematic entire configuration of a fuel injection apparatus (aninjector) of a first embodiment which is one example of a fuel supplyapparatus of the present invention will be explained referring to FIGS.1 and 2. FIG. 1 is a sectional view of the fuel injection apparatus inthe present embodiment. FIG. 2 is an enlarged sectional view of a valveseat member and its surrounding. As shown in FIG. 1, the fuel injectionapparatus 1 includes a main body 10, a valve element 12, a valve seatmember 14, a compression spring 16, a separation suppressing member 80,and others.

The main body 10 includes a housing 24, a stator core 26, a casing 28,an electromagnetic coil 30, and others. This main body 10 accommodatesthe valve element 12, the valve seat member 14, the compression spring16, and others. In the main body 10, there is formed a fuel passage 34in which a gas fuel will flow.

The housing 24 is configured to surround a part of the stator core 26and a part of the casing 28. The housing 24 is made of resin in whichthe electromagnetic coil 30 is embedded. This electromagnetic coil 30 isplaced in a position surrounding the stator core 26. The electromagneticcoil 30 is a drive part to drive the valve element 12 to be brought incontact with and separated from the valve seat member 14. The housing 24is further provided with a connector part 38 provided therein with aplurality of terminal pins 36. These terminal pins 36 are electricallyconnected to the electromagnetic coil 30.

The stator core 26 is placed on an opposite side to the valve seatmember 14 with respect to the valve element 12. The stator core 26 has anearly cylindrical shape (including an exact circular cylindrical shape,an elliptic shape, etc.) and is formed at its center with a through hole26 a. This through hole 26 a constitutes an upstream part of the fuelpassage 34. An upstream end (an upper end in FIG. 1) of the stator core26 can be connected to an external fuel supply section (not shown). Thestator core 26 is made of soft magnetic material (e.g., electromagneticstainless steel). It is to be noted that the gas fuel in the fuelpassage 34 flows by passing through a filter member 20 for removingforeign substances contained in the fuel.

The casing 28 is placed in a position on a downstream side (a lower sidein FIG. 1) of the stator core 26 in a flowing direction of gas fuel. Thecasing 28 has a nearly cylindrical shape and is formed at its centerwith a through hole 28 a. The casing 28 is made of soft magneticmaterial (e.g., electromagnetic stainless steel). The casing 28accommodates, in the through hole 28 a, the valve element 12 and thevalve seat member 14.

The valve element 12 is placed in a position on an upstream side (anupper side in FIG. 1) of the valve seat member 14 in the gas fuelflowing direction. The valve element 12 is made of soft magneticmaterial (e.g., electromagnetic stainless steel). This valve element 12is urged by the compression spring 16 toward the valve seat member 14.

The valve element 12 has a closed-bottom cylindrical shape (a nearlycylindrical shape), namely, is formed in a shape having a cylindricalportion and a closed bottom portion. To be concrete, the valve element12 includes a cylindrical portion 40 having a nearly cylindrical shapecorresponding to the cylindrical portion of the closed-bottomcylindrical shape and a seal portion 42 having a nearly disc-like shapecorresponding to the closed-bottom portion of the closed-bottomcylindrical shape, and others. The cylindrical portion 40 is formed witha flow passage 44 which is part of the fuel passage 34. The seal portion42 is adapted to come into and out of contact with the valve seat member14 and is made of rubber, resin, and others.

The valve seat member 14 is placed in a position on a downstream side (alower side in FIG. 1) of the valve element 12 in the gas fuel flowingdirection within the through hole 28 a of the casing 28. The valve seatmember 14 is a component with which the valve element 12 comes into andout of contact. The valve seat member 14 is fixed to the casing 28selectively by press-fitting in the casing 28, by welding to the casing28 over the whole circumference, or by both press-fitting and welding.

The valve seat member 14 includes a seat portion 56 and a peripheralwall portion 58. The seat portion 56 is formed in a disc-like shape.This seat portion 56 includes a seat surface 60, a discharge hole 62,and others. The seat surface 60 is a surface located on a side of theseat portion 56 facing the valve element 12. With this seat surface 60,the seal portion 42 of the valve element 12 will be brought into or outof contact. The discharge hole 62 is a through hole formed to axiallypenetrate through a radially central portion of the seat portion 56. Thedischarge hole 62 is a flow passage of gas fuel. The peripheral wallportion 58 is formed in a cylindrical shape extending from the seatportion 56 along the axial direction of the valve element 12 toward anopposite side from the valve element 12. Accordingly, the peripheralwall portion 58 is internally provided with an open portion 59 with alarger diameter than a diameter of the discharge hole 62. This openportion 59 is communicated with a lower end of the discharge hole 62.

Further, the open portion 59 is provided therein with a separationsuppressing member 80 as shown in FIG. 2. This separation suppressingmember 80 is fixed in the open portion 59 selectively by press-fittinginto, welding to, or caulking to the open portion 59. The separationsuppressing member 80 serves to suppress the gas fuel flow or streamfrom getting separated in flowing out into the open portion 59 throughthe discharge hole 62. In the present embodiment, the separationsuppressing member 80 is made of a porous body such as a sintered filterand is filled in the open portion 59.

In the present embodiment, the separation suppressing member 80 isfilled almost over the entire area within the open portion 59, but theseparation suppressing member 80 is not necessarily fixed all over theentire region and instead may be filled partly in the open portion 59.In the case of using such a partly filled separation suppressing member80, it has to be placed in at least an area communicated with thedischarge hole 62 (an uppermost side in the open portion 59).

In the present embodiment, furthermore, the separation suppressingmember 80 is made of a porous body. As an alternative, the separationsuppressing member 80 may be made of a mesh body. In the case of usingsuch a mesh separation suppressing member 80, at least the outerperipheral portion of this separation suppressing member 80 has only tobe made of a mesh material (i.e., a basket or cage shaped mesh body).This separation suppressing member 80 may also be further provided witha mesh body inside the mesh outer peripheral portion. As anotheralternative, the separation suppressing member 80 may be made of aplurality of mesh bodies overlapping one on another. In this case ofusing the overlapping mesh bodies, these mesh bodies may be different inmesh size.

Next, operations (actions) of the fuel injection apparatus 1 will beexplained. While the electromagnetic coil 30 is not supplied with powerthrough the terminal pins 36 of the connector part 38, that is, duringvalve closing, the seal portion 42 of the valve element 12 is held incontact with the seat surface 60 of the valve seat member 14 by theurging force of the compression spring 16 as shown in FIG. 1. Thus, thedischarge hole 62 of the valve seat member 14 is shut off from the fuelpassage 34. Accordingly, the gas fuel is not allowed to discharge out ofthe fuel injection apparatus 1 through the discharge hole 62.

On the other hand, while the electromagnetic coil 30 is supplied withpower, or energized, through the terminal pins 36 of the connector part38, that is, during valve opening, the electromagnetic coil 30 generatesmagnetic fields, thereby exciting the valve element 12 and the statorcore 26. Then the valve element 12 and the stator core 26 attract eachother, so that the valve element 12 moves toward the stator core 26.Specifically, the seal portion 42 of the valve element 12 is separatedfrom the seat surface 60 of the valve seat member 14. Accordingly, thedischarge hole 62 of the valve seat member 14 gets communicated with thefuel passage 34. This allows the gas fuel flowing in the fuel passage 34to flow in the discharge hole 62 and therefrom flow to the outside ofthe fuel injection apparatus 1.

At that time, since the passage cross-sectional area abruptly changesfrom the discharge hole 62 to the open portion 59, the gas fuel flow orstream may be separated, leading to generation of gas flow sound(noise). In the fuel injection apparatus 1, however, the gas fueldischarged from the discharge hole 62 flows in the separationsuppressing member 80 before acceleration and impinges on the porousbody (or mesh body). Accordingly, the gas fuel is decelerated and alsodispersed, so that separation of the gas fuel flow in the open portion59 can be reliably suppressed. This can surely reduce the gas flow soundresulting from the separation of gas fuel flow.

Herein, modified examples or variations of the first embodiment will beexplained referring to FIGS. 3 to 6. FIG. 3 is a view of a firstmodified example, FIG. 4 is a view of a second modified example, FIG. 5is a view of a third modified example, and FIG. 6 is a view of a fourthmodified example. In these modified examples, similar or identical partsto those in the first embodiment are assigned with the same referencesigns as those in the first embodiment and their details are notrepeatedly explained. Thus the following explanation is given with afocus on differences from the first embodiment.

In the first modified example, as shown in FIG. 3, a separationsuppressing member 80 a placed in the open portion 59 is designed suchthat a downstream-side end face 81 is spherical. The thus configuredseparation suppressing member 80 a can disperse gas fuel flowing out ofthe separation suppressing member 80 a. According to the first modifiedexample, therefore, the separation of the gas fuel flow can be furtherinhibited and thus the gas flow sound resulting from the separation ofgas fuel flow can be further reduced.

In FIG. 3, a spherical portion (the downstream-side end face 81) of theseparation suppressing member 80 a spherically protrudes downward fromthe open portion 59. As an alternative, the spherical portion may bespherically recessed upward in the open portion 59.

In the second modified example, as shown in FIG. 4, a separationsuppressing member 80 b is placed in the discharge hole 62, not in theopen portion 59. This configuration can decelerate the fuel gas in thedischarge hole 62. Further, The separation suppressing member 80 b isalso designed such that a downstream-side end face 81 is spherical as inthe first modified example. Accordingly, the gas fuel flowing out of theseparation suppressing member 80 b (i.e., the discharge hole 62) can bedispersed in the open portion 59. In the second modified example,consequently, the separation of the gas fuel flow in the open portion 59can also be suppressed and thus the gas flow sound resulting from theseparation of gas fuel flow can be further reduced.

In the third modified example, as shown in FIG. 5, a separationsuppressing member 80 c is placed so as to partially protrude from theopen portion 59 and a blocking plate 82 is provided on a downstream-sideend of the separation suppressing member 80 c. The blocking plate 82serves to block outflow of gas fuel from the downstream-side end face ofthe separation suppressing member 80 c. The gas fuel having passedthrough the separation suppressing member 80 c is thus directed by theblocking plate 82 to flow out from a peripheral surface of a protrudingportion of the separation suppressing member 80 c from the open portion59. Accordingly, the gas fuel flowing out of the separation suppressingmember 80 c can be reliably dispersed. According to the third modifiedexample, therefore, the separation of the gas fuel flow can be furthersuppressed and thus the gas flow sound resulting from the separation ofgas fuel flow can be further reduced.

Herein, if a protruding amount (a protruding height) of the separationsuppressing member 80 c from the open portion 59 is small, there is apossibility that a necessary flow amount of fuel gas may not be ensured.In the third modified example, therefore, the protruding amount (theprotruding height) H of the separation suppressing member 80 c is set to1/8 to 1/2 of the diameter D of the separation suppressing member 80 c(i.e., H=D/8 to D/2). This setting of the protruding amount H is givenfor the reason that, if the protruding amount H is smaller than D/8, theseparation suppressing member 80 c may not provide a necessary flowamount of fuel gas, while if the protruding amount H is larger than D/2,the separation suppressing member 80 c may not achieve a dispersioneffect of fuel gas by the blocking plate 82.

In the first to third modified examples, the separation suppressingmembers may be made of any one of a porous body and a mesh body.

In the fourth modified example, a separation suppressing member 80 d ismade of a porous body and, as shown in FIG. 6, is formed with a throughhole 83 communicated with the discharge hole 62 and extending in a gasfuel flowing direction. The separation suppressing member 80 d includingthe through hole 83 can prevent abrupt changes in passagecross-sectional area and suppress acceleration of gas fuel by making gasfuel pass through the through hole 83. In the fourth modified example,accordingly, the separation of the gas fuel flow can be suppressed andthus the gas flow sound resulting from the separation of gas fuel flowcan be reduced. The diameter d2 of the through hole 83 is set to equalto or less than twice the diameter d1 of the discharge hole 62(d2≦2×d1). This setting is given for the reason that if the diameter d2of the through hole 83 exceeds twice the diameter dl of the dischargehole 62, the through hole 83 could not suppress the acceleration of gasfuel.

According to the fuel injection apparatus 1 in the first embodimentexplained in detail above, since the separation suppressing member 80(80 a to 80 d) is placed in the open portion 59 (or in the dischargehole 62), the gas fuel discharged from the discharge hole 62 flows inthe separation suppressing member 80 (80 a to 80 d) before acceleratingand thus is decelerated and dispersed to flow out of the fuel injectionapparatus 1. Therefore, the separation of the gas fuel flow in the openportion 59 can be prevented and the gas flow sound resulting from theseparation of gas fuel flow can be reduced.

Second Embodiment

A schematic entire configuration of a fuel supply unit of a secondembodiment will be explained below referring to FIGS. 7 to 9. FIG. 7 isa sectional view of the fuel supply unit of the second embodiment, andFIGS. 8 and 9 are enlarged sectional views of a leading end and itssurrounding in a fuel injection apparatus provided in the fuel supplyunit. The fuel supply unit 124 is provided, as shown in FIG. 7, aninflow block 144, an outflow block 146, fuel injection apparatuses(injectors) 148, a secondary pressure sensor 150, a tertiary pressuresensor 152, and others.

The inflow block 144 is a component for distributing fuel gas to thefuel injection apparatuses 148. This inflow block 144 includes an inflowpassage 158, a cavity 160, inflow ports 162, a sensor hole 164, andothers.

The inflow passage 158 is a passage in which the fuel gas will flow. Inthe cavity 160, the fuel injection apparatuses 148 are arranged at apredetermined spacing from each other. The inflow ports 162 are formedto connect the inflow passage 158 and the cavity 160. In each of theinflow ports 162, an inlet pipe 148 b provided at an inlet of thecorresponding fuel injection apparatus 148 is fitted. In the exampleshown in FIG. 7, the inlet pipes 148 b of three fuel injectionapparatuses 148 are arranged in parallel side by side to open in theinflow passage 158. In the sensor hole 164, the secondary pressuresensor 150 is fitted. The inflow block 144 is secured to the outflowblock 146 with bolts 154.

The outflow block 146 is a component for making streams of the fuel gasinjected from the fuel injection apparatuses 148 merge or join into onestream. This outflow block 146 is formed with an outflow passage 168,flow restricting members 169, a sensor hole 172, and others. The outflowblock 146 has a two-block configuration.

The outflow passage 168 is a passage in which the fuel gas injected fromthe fuel injection apparatuses 148 will be discharged. The flowrestricting members 169 are arranged within the outflow passage 168 inpositions corresponding to the fuel injection apparatuses 148. Theseflow restricting members 169 are configured to forcibly cause the gasfuel flowing out from the discharge holes 62 of the fuel injectionapparatuses 148 into the outflow passage 168 to flow in a radialdirection of each discharge hole 62, that is, to be dispersed. Thetertiary pressure sensor 152 is fitted in the sensor hole 172.

In the present embodiment, herein, the flow restricting members 169 andthe outflow block 146 are made as separate components. As analternative, the flow restricting members 169 may be integrally formedwith the outflow block 146. In this case, the flow restricting membercan be provided easily and inexpensively. This configuration can furtherachieve a reduced number of components as compared with theconfiguration provided with separate flow restricting members andfurther eliminate the need for a work to join the flow restrictingmembers, thus leading to improved production efficiency. Accordingly, afuel supply unit can be provided at lower cost than the foregoingconfiguration.

The fuel injection apparatuses 148 are held between the inflow block 144and the outflow block 146. Each of the fuel injection apparatuses 148 isplaced with each leading end (a leading end located on a side close to adischarge hole 62) slightly protrudes into the outflow passage 168 toface the corresponding flow restricting member 169 as shown in FIGS. 7and 8. It is to be noted that the fuel injection apparatuses 148 may beplaced so that their leading ends are flush with the inner surface ofthe outflow passage 168 as shown in FIG. 9.

The fuel injection apparatuses 148 are connected with the inflow passage158 and the outflow passage 168 to adjust a flow rate of fuel gas. Thefuel injection apparatuses 148 are identical in basic structure to thefuel injection apparatus 1 of the first embodiment but are different inthat the valve seat member has no open portion and is formed with onlythe nozzle hole (the discharge port 62) and that no separationsuppressing member is provided. The present embodiment may also employthe fuel injection apparatus 1 of the first embodiment as each of thefuel injection apparatuses 148.

In the example shown in FIG. 7, the fuel supply unit 124 includes threefuel injection apparatuses 148. The number of fuel injection apparatuses148 is not particularly limited and may be two or four or more.

Herein, the positional relationship between the fuel injectionapparatuses 148 and the flow restricting members 169 will be brieflyexplained. As shown in FIG. 8, the flow restricting member 169 is placedsuch that the interval (distance) S between the leading end of the fuelinjection apparatus 148 and the flow restricting member 169 is 1/4 to1/2 of the diameter d1 of the discharge hole 62 in the fuel injectionapparatus 148 (S=d1/4 to d1/2). This setting of the interval S in such arange is based on the reason that if the interval S is smaller thand1/4, a necessary amount of fuel gas may not be provided, while if theinterval S is larger than d1/2, a dispersion effect of fuel gas may notbe achieved.

In the thus configured fuel supply unit 124, fuel gas introduced in theinflow passage 158 is supplied into the outflow passage 168 through thefuel injection apparatuses 148. At that time, since the passagecross-sectional area abruptly changes from each fuel injection apparatus148 to the outflow passage 168, the gas fuel flow or stream may beseparated, leading to generation of gas flow sound (noise).

However, in the fuel supply unit 124, the gas fuel discharged from thedischarge holes 62 of the fuel injection apparatuses 148 impinges on theflow restricting members 169 before accelerating and thereby the gasfuel is directed to flow in the radial direction of the discharge holes62. Thus, the gas fuel discharged from the discharge holes 62 of thefuel injection apparatuses 148 is dispersed within the outflow passage168. Accordingly, the gas fuel injected from the fuel injectionapparatuses 148 is decelerated and dispersed by the flow restrictingmembers 169. Consequently, separation of the gas fuel flow in theoutflow passage 168 can be reliably suppressed. This can surely reducethe gas flow sound resulting from the separation of gas fuel flow.

According to the fuel supply unit 124 in the second embodiment explainedin detail above, since the flow restricting members 169 are provided inthe outflow passage 168 so as to face the discharge holes 162 of thefuel injection apparatuses 148, the gas fuel injected from the dischargeholes 162 are decelerated and dispersed by the flow restricting members169 before acceleration. Accordingly the separation of the gas fuel flowin the outflow passage 169 can be reliably suppressed and thus the gasflow sound resulting from the separation of gas fuel flow can be surelyreduced.

The foregoing embodiments are mere examples and do not give anylimitations to the present invention. The present invention may beembodied in other specific forms without departing from the essentialcharacteristics thereof. For instance, the foregoing embodiments showthe example where hydrogen gas is supplied as the fuel gas. The presentinvention is also applicable to an apparatus configured to supply gasfuel (e.g., natural gas) other than hydrogen.

REFERENCE SIGNS LIST

-   1 Fuel injection apparatus-   12 Valve element-   14 Valve seat-   34 Fuel passage-   59 Open portion-   60 Seat surface-   62 Discharge port-   80, 80 a-80 d Separation suppressing member-   81 Downstream-side end face-   82 Blocking plate-   83 Through hole-   124 Fuel supply unit-   144 Inflow block-   146 Outflow block-   148 Fuel injection apparatus-   158 Inflow passage-   168 Outflow passage-   169 Flow restricting member

What is claimed is:
 1. A fuel supply apparatus having a discharge holeand configured to adjust a flow rate of fuel gas and inject and supplythe fuel gas through the discharge hole, the apparatus comprising: anopen portion formed with a larger diameter than the discharge hole andcommunicated with a downstream end of the discharge hole; and aseparation suppressing member configured to suppress generation ofseparation of flow of the gas fuel when the gas fuel flows out from thedischarge hole into the open portion, and wherein the separationsuppressing member is placed in one of the open portion and thedischarge hole.
 2. The fuel supply apparatus according to claim 1,wherein the separation suppressing member is made of one of a porousbody and a mesh body.
 3. The fuel supply apparatus according to claim 1,wherein the separation suppressing member includes a downstream-side endface formed in a spherical shape.
 4. The fuel supply apparatus accordingto claim 1, wherein the separation suppressing member includes a partprotruding from the open portion or the discharge hole, and theseparation suppressing member is provided, on its downstream-side end,with a blocking plate for blocking outflow of the gas fuel from adownstream-side end face of the separation suppressing member.
 5. Thefuel supply apparatus according to claim 1, wherein the separationsuppressing member is made of a porous body, and the porous body isplaced in the open portion and has a through hole extending in a flowingdirection of the gas fuel, the through hole being communicated with thedischarge hole.
 6. A fuel supply unit including at least one fuelinjection apparatus configured to adjust a flow rate of gas fuel andinject the gas fuel and an outflow passage in which the gas fuelinjected from the fuel injection apparatus is to be discharged, whereinthe fuel supply unit comprises a flow restricting member configured toforcibly direct the gas fuel discharged from a discharge hole of thefuel injection apparatus into the outflow passage to flow in a radialdirection of the discharge hole.
 7. The fuel supply unit according toclaim 6, wherein the flow restricting member is integrally formed withthe outflow passage.